So now we’re all just sitting around waiting for Donald Trump to pivot. As in, change. We demand and expect that of party front-runners at this stage of a primary campaign.

“You’re going to see Trump pivoting,” promised Ben Carson, who knows a thing or two about Trump pivoting; Trump, who described Carson as “a special, special person” upon receiving his endorsement last week, had previously compared Carson to a child molester.

Our political culture is governed by a set of tropes and traditions. Even if these tropes and traditions are often violated — and Trump has done so again and again — everybody clings to them. The “pivot” is a timely example. It refers to the expectation that at some point a leading presidential candidate will transform himself into a more suitable version of a likely nominee. He will “pivot” his attention away from his hard-core base of loyalists in favor of the broader general electorate. He will, in Trump’s case, scale back his hell-raiser, insult-monger bit and become more “presidential.” No doubt Trump’s pivot will be beautiful and be instantly recognized as one of the great pivots of all time. There are indications that it is starting already.

He is also toning down the nasty he has unleashed over the last eight months upon the “weak” party leaders and “stupid” lawmakers and “useless” political hacks that have made such a disaster of things. In return, many of these same weak, stupid and useless dignitaries will note that their Rottweiler is finally showing signs of being house-trained. Lots of them will probably fall for Trump’s pivot, too.

But there is also something openly absurd about the concept of a Trump pivot. Certainly he is capable of changing his views — often and with breathtaking speed. But really, how do you pivot away from saying that Mexicans are rapists? (Will he negotiate “great deals” with more moderate Mexican rapists?) If your campaign is a cult of personality, how can you modulate that personality and still have the cult? In Trump’s case, a “pivot” would constitute a complete overhaul of his very essence.

Not everyone will buy Trump’s pivot, of course. “Nothing makes Trump more acceptable today than yesterday or last week – or six months ago,” the Washington Post columnist Kathleen Parker wrote this month. “He is still a boastful, volatile, misogynistic, race-baiting, willfully and strategically ignorant, exploitative fear-monger who is guided by profit over principle, and whose hair-trigger temperament has the world on edge.”

But Trump will still be happy to humor the rest of us. He will embark on a pivot and then wait for everyone to acknowledge his growth, maturity and statesmanship, which you know they will. “What Trump is saying, in his own weird way is that he gets it,” Chris Cillizza wrote in The Washington Post after Trump said it was important to re-elect G.O.P. senators and congressmen.

Of course Trump “gets it.” Whether or not he “means it” or that anyone will “buy it” is another question. But you know the pivot is coming because Trump has been telegraphing it explicitly for weeks. “As I get closer and closer to the goal, it’s gonna get different,” he told Greta Van Susteren last month. “I will be changing very rapidly. I’m very capable of changing to anything I want to change to.”

Candidates are typically subtler than this. It’s better to not insult everyone’s intelligence too blatantly, as Mitt Romney’s spokesman Eric Fehrnstrom learned in March 2012 after he said Romney, then the G.O.P. front-runner, would “hit a reset button” after he pivoted to the general-election campaign. “It’s almost like an Etch-A-Sketch,” Fehrnstrom said. “You can kind of shake it up, and we start all over again.”

Romney suffered great ridicule for this. His chief remaining challenger, Rick Santorum, released a photo of himself holding up an Etch-a-Sketch with a caption, “studying up on [Romney’s] policy positions.” Fehrnstrom had violated a big rule of the game: Don’t throw the idiocy of the unwritten rules in everyone’s face.

But Trump follows no such rules, cardinal, unwritten or otherwise. That’s part of the perverse beauty of him. He can be breathtakingly forthcoming about the scam he is attempting to put over. “At the right time, I will be so presidential that you’ll call me and you’ll say, ‘Donald, you have to stop that, it’s too much,’” Trump told Sean Hannity last week. “I can be presidential,” he concluded.